Spark arrester



Jan. 2, 1945 A, CANNON 2,366,314

SPARK ARRESTER -Filed June 10, 1943 3 Sheets-Sheet 1 Jesse H Ch/v/vaw1945- J. A. CANNON 2,366,314

SPARK ARRESTER Filed June 10, 1945 3 Sheets-Sheet 2 :55 I (o 1/6556?ChMvo/v Jan. 2, 1945. J. A. CANNON SPARK ARRESTER Fil d June 10, 1943 3Sheets-Sheet 3 Jassz 6? Ck/v/voxv Patentecl Jan. 2, 1945 UNITEDSTATESPATENT orncs.

2,366,314 SPARK ARRESTER Jesse A. Cannon, Jamestown, N. Dak., assignorof one-half to Arthur J. Witham, Jamestown,

N. Dak.

Application June10, 1943, Serial No. 490,377

Claims. (Cl. 110- 122) the smoke box and then rearwardly through thespark arrester and finally to the lift pipe of the stack. It is furtherintended to divide the smoke after it has reached the front end of thesmoke box so that a portion travels directly rearwardly and thence intothe lift pipe, and the remainder travels rearwardly and over the upperportion of the spark arrester entering the spark arrester through theopen rear, and thence to the lift pipe. In keeping with this objective,it is intended to provide a spark arrester having top and bottom plates,side walls, but open front and rear ends. In order to ensure circuitousflow of smoke, cinders, and sparks from the flue sheet into the sparkarrester, it is proposed herein to baffle the rear of the spark arresterto prevent the flow of smoke from the flue sheet directly for- Wardlyinto the rear of the sparkarrester.

Another object is to provide a spark' arrester having open front andrear ends and to provide a plurality of spaced deflecting bafilesangularly disposed across the openings, such deflecting baflles beingdisposed in vertical, non-parallel planes. Furthermore, an object is todispose the baffles so that smoke entering the main section of the sparkarrester by passing therebetween will flow substantially directly to thelift pipe and will not swirl cyclically or vertically. It is accordinglyintended to dispose the deflecting baffles so that. the force of smokeentering between the bafiles from the front, for instance, will bebalanced by the directive force of the smoke entering between the rearbafiles. Itis also intended to dispose the deflecting baffies at such anangle with respect to one another so that the larger portion of thesmoke will flow substantially radially to the center of the assembly.

More particularly, it is herein proposed to provide a series of bafilesacross the front and rear openings of the arrester chamber, and todispose each baflie at a greater angle to the infl'owing gases than thepreceding baffie, so that gases and cinders impinging upon the face ofone baflle will be deflected to the rear of the'preceding baflle.

Also, it is intended to arrange the baffles to counteract and break upany swirling currents within the chamber.

Another object is to provide a spark arrester having a plurality ofbaffles so disposed that hot cinders and sparks will not impingeforcefully directly upon the baffles, thereby avoiding cutting of thebaflle material. Additionally, it is intended to arrange the arresterassembly so that any large cinders will never enter the interior of thear-# rester, but will be pulverized in the front end of thesmoke boxthus facilitating cleaning.

Summarizin the objectives, it is intended to provide improved steamingqualities in a 1oco-' motive, equal distribution of draft over theentire grate area, to ease the cleaning of the smoke box of thelocomotive, to reduce amount of black smoke emitted from the smokestack, and to reduce cinder cutting. These and other objectives will beapparent in the following specification and drawings, in which:

Fig. 1 is a vertical longitudinal section of the spark arrester takenalong line I--l of Fig. 3;

Fig. 2 is a front elevation taken from line 2-2 of Fig. 1;

Fig. 3 is a plan view;

Fig. 4 is a detailed enlargement along line 4-4 of Fig. 2;,,

Fig. 5 is a detailed enlargement along line 5--5 of Fi 3;

Fig. 6 is a detailed enlargement along line 66 of Fig. 3, and,

Fig. 7 is an isometric view of the spark arrester removed from the smokebox.

Referring now to the drawings in which like reference numerals denotethe same or similar parts, the front end 2 of a locomotive is shown indash lines, the front end conventionally enclosing the smoke box havinglift pipe 4 of the smoke stack, steam exhaust 6 below and spaced fromthe ift pipe, throttle header 8 and steam pipes Ill. The inventivestructure includes a vertical rear bafile l2 spaced forwardly from andparallel to the front flue sheet of the boiler. The flanged top of rearbaffle I 2 is welded to the throttle header shown at I 3, and an upperpartition I4 is welded between throttle header 8 and the top of thesmoke box as shown at l5. The side edges of baffle I2 and partition Mare curved to engage snugly the inner side wall of the smoke box so asto extend across the box.

haust pipe 6 to which it is rigidly secured. The .top comprises a headsheet l8 having a circular opening l9 closely surrounding lift pipe 4.Preferably, a circular flange is bolted around the opening 19 and weldedto a band sweated to the lift pipe. The bottom and top head sheetscomprise a number of strips of sheet metal 20 and seam battens 22, eachbatten being bolted to one sheet 20 as shown at 24 and secured to theadiacent sheet by welding 26. The battens are disposed on the outersurface of head sheets thus providing a smooth inner surface. openingsmay be cut in the head sheets, particularly adjacent edges, to allow thesteam pipes to pass therethrough. i

As seen best in Figures 3 and 7, the central chamber of the sparkarrester is further enclosed V the surfaces of the deflecting baflleslie generally.

perpendicular to radii of openings [1 and I9, each baiiie in a series,going from 34 to 40, is disposed at a slightly greater angle toinflowinggases than the preceding one. By this arrangement gasesimpinging upon the face of one baffle are deflected against the rear ofthe preceding one, thus pulverizing any cinders, entrained'in theflowing gases. Likewise the open rear of the arrester chamber isprovided with a series of deflecting baflles 42, 4, 45, and 48, alsoangularly disposed to deflect incoming gases to the center of thechamber. The deflecting bafiles are formed of sheet metal securedbetween the bottom head sheets by seams, one of which is detailed inFigure 4c and which includes a square bar 50 having the top surfacethereof welded as at 52 to the baffle and as at54 to the head sheet.

Referring now to Figure 1, it will be seen that gases flowing forwardlyfrom the front flue sheet are partially blocked by baffles l2 and I4 sothat flow must first occur underneath the spark arrester and forwardlyto the front of the smoke box. As indicated by the arrows, the flowstream is split, some of the gases flowing directly into the arresterthrough the front end of chamber, and the gases which do not enter. thevfront of the arrester pass upwardly and rearwardly around the lift pipeto the. front of baflies l4 and i2 and thence downwardly and in throughthe rear end of the arrester. As shown best. in Figure 3 by the arrows,the gases passing through the front end of the arrester are deflecteddirectly towards the center of the chamber with. the exception of thosepassing between the straight front porticn 32 of the side wall 3l1andbaffle 34. In this casethe flow is around the side of the baffle to?rear baffle 42 and then inwardly towards the center. Any tendency forthe gases tocontinue ,to swirl vertically is overcome by thestraightening effect of the gases deflected by baffle ii. and thosesucceeding. Likewise the gases passing between baflie 48 and side wall28 are directed inwardly by gases deflected from baflie All. Once thecentral portion of the chamber is reached. the gases pass upwardlyintothe. lift pipe partially entrained in the steam from exhaust- 5.

It. will. thus be. seen that, in operation gases will pass uniformlyfrom. the entire area of the front flue sheet and around the bottom othe Suitable.

spark arrester, thus providing an even steady draft. Upon reaching thefront of the smoke box, the hotter gases rise to the top and pass aroundover the top thus delaying contact with the deflector baffles untiltheir heat is partially dissipated. Meanwhile pulverization of cinderswill have occurred by striking engagement with baffle l2 and furtherpulverization is achieved by striking against the surfaces of thedeflecting bafiies.

One embodiment of the invention has been described in detail, but theconcept is not to be limited to the specific structure disclosed sinceit may apply to all modifications and substitutionswithin the scope ofthe following claims.

I claim:

1. In combination with the smoke box, exhaust nozzle and lift pipe of alocomotive, a spark arrester comprising means forming a chamber betweenthe pipe and nozzle and having spaced top and bottom walls spaced fromthe top and bottom of the smoke box and extending substantiallyth'ereacross, spaced side walls cooperating with said top and bottomwalls to form a chamber open at'the front and rear ends, and a pluralityof vertically disposed baffles mounted at irregularly spaced intervalsacross said open front and rear ends, the baffles being so angularlydisposed with respectto one another and with respect to the chamber asto direct gases entering therebetween generally radially inwardlytowards the center of the chamber.

2. The combination claimedin claim 1, the bottom wall extendingrearwardly of the top wall,-

and a baflie wall extending upwardly from the rear. of said bottom walland across said chamber, whereby to prevent direct forward passage ofgases from the rear of said spark arrester directly into saidchambentherear edge of the top wall being spaced from the. rear wall, whereby toallow gases to pass rearwardly over the top wall and thence into therear end of the chamber.

3. In combination with a smoke box, exhaust nozzle and lift pipe of alocomotive, a spark arrester comprising a chamber between said nozzleand pipe, said chamber being closed at the sides, top and bottom andopen at'its rear, said arrester being spaced from the top, front, rearand bottom of. the smoke box, andbaflie means disposed rearwardly of theopen rear forming a passage from the rear of the smoke box beneath thearrester, then. upwardly in front thereof, then rearwardly over the topof the arrester, then downwardly, and. thence forwardly through the openrear of the arrester, whereby to prevent passage of gases from the rearof said smoke box directly into the rear of said arrester.

4. In combination with the smoke box, exhaust nozzle and lift pipe of alocomotive, a spark 'arrester comprising a generally rectangular bottomsheet adapted to extend. across the smoke box and havinga substantiallycentral opening to receive the" steam exhaust. pipe, vertical transverserear baffle means extending upwardly from the rear of said bottomsheetto the top of said smoke box, an opposed pair of verticalcontinuous side walls curved to formv arcs of a circle extendinggenerally fore and aft and being spaced inwardly from the margins of thebottom sheet, and leaving said arrester open at the front and rear, atopsheet spaced from the top of the. smoke box and having a generallycircular rear portion fit.- ting theside walls anda rectangular,visor-like front portion overlying the front of said bottom sheet, therear edge of. said top sheet being spaced rearwardly from said. rearbaffle means, said top 5. The combination claimed in claim 4, the

deflecting bafiles extending, in the direction from the outer to theinner edges thereof, counterclockwise of the central openings, thebaifies in each series, in clockwise order, being at successivelyincreasing angles to the infiowing gases,

whereby gases impinging upon the front face of a baffle are deflected tothe rear face of the preceding baflie, and thence clockwise to theinterior of the chamber.

' JESSE A. CANNON.

